Capital value of shared wind-to-hydrogen infrastructure in co-located green ammonia and liquefied hydrogen plants

Co-locating green liquefied hydrogen (LH 2 ) and ammonia (NH 3 ) production creates a shared-infrastructure capital-allocation problem. This study develops a multi-year mixed-integer linear programming (MILP) framework to evaluate how an imposed LH 2 requirement changes the design, service, and installed-capital requirements of an off-grid wind-powered NH 3 platform. The model uses chronological ERA5 wind data from Chile’s Magallanes region and represents shared wind generation, desalination, electrolysis, and hydrogen buffering together with the dedicated NH 3 and LH 2 conversion and storage pathways. Four planning scenarios are compared: an NH 3 -only benchmark, fixed-budget co-production, protected-NH 3 co-production through marginal capacity expansion, and standalone greenfield LH 2 production. The analysis distinguishes the service tradeoff created when LH 2 is introduced under a fixed capital budget from the additional investment required when benchmark NH 3 service is protected. The results show that co-location reduces the incremental capital required to provide LH 2 relative to a standalone greenfield system, but this advantage does not arise uniformly from all shared assets. Instead, the integrated design combines expansion of the common wind-to-hydrogen platform with lower requirements for parts of the dedicated LH 2 pathway, particularly liquefaction capacity. The principal capital-value conclusions remain robust to constrained downstream process flexibility, stronger NH 3 service protection, hourly temporal resolution, spatial wind-resource variation, wind-plant losses, turbine representation, LH 2 service scale, and major CAPEX assumptions. The findings provide plant-gate, CAPEX-centered planning insights into when co-location can reduce the incremental infrastructure required to introduce LH 2 production while maintaining renewable NH 3 service.